Searching and placeholders

ABSTRACT

Aspects of the subject matter described herein relate to file system placeholders. In aspects, placeholders may be used by a client to represent remote file system objects. The placeholders may include metadata, searchable text, and may also include none, some, or all of the content of the represented remote file system objects. Search data from the placeholders is integrated into a local search database of the client such that the client is able to satisfy queries and identify relevant local and remote file system objects even when the client is offline with respect to remote storage.

RELATED APPLICATIONS

This application is a continuation patent application of copendingapplication with Ser. No. 13/873,264, (attorney docket no. 339010.01)filed Apr. 30, 2013, entitled “SEARCHING AND PLACEHOLDERS”, which is nowallowed. The aforementioned application(s) are hereby incorporatedherein by reference.

BACKGROUND

Today, it is not uncommon for a family or even a single person to havemultiple computing devices such as a desktop computer, a laptop, asmartphone, an internet-enabled television, a set top box, a gamingdevice, a reading tablet, and so forth. In addition, a user may havethousands of files that include pictures, audio, documents, and the likethat are stored in the cloud or elsewhere. A user may want to access thefiles from one or more of the computing devices available to the user.

Downloading all of the user's content to each of the user's devices maynot be possible as some devices may have very limited storage.Furthermore, even when a computing device has extensive storage,downloading the content to the computing device may consume considerablebandwidth, be costly, and take a long time.

The subject matter claimed herein is not limited to embodiments thatsolve any disadvantages or that operate only in environments such asthose described above. Rather, this background is only provided toillustrate one exemplary technology area where some embodimentsdescribed herein may be practiced.

SUMMARY

Briefly, aspects of the subject matter described herein relate to filesystem placeholders. In aspects, placeholders may be used by a client torepresent remote file system objects. The placeholders may includemetadata, searchable text, and may also include none, some, or all ofthe content of the represented remote file system objects. Search datafrom the placeholders is integrated into a local search database of theclient such that the client is able to satisfy queries and identifyrelevant local and remote file system objects even when the client isoffline with respect to remote storage.

This Summary is provided to briefly identify some aspects of the subjectmatter that is further described below in the Detailed Description. ThisSummary is not intended to identify key or essential features of theclaimed subject matter, nor is it intended to be used to limit the scopeof the claimed subject matter.

The phrase “subject matter described herein” refers to subject matterdescribed in the Detailed Description unless the context clearlyindicates otherwise. The term “aspects” should be read as “at least oneaspect.” Identifying aspects of the subject matter described in theDetailed Description is not intended to identify key or essentialfeatures of the claimed subject matter.

The aspects described above and other aspects of the subject matterdescribed herein are illustrated by way of example and not limited inthe accompanying figures in which like reference numerals indicatesimilar elements and in which:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram representing an exemplary general-purposecomputing environment into which aspects of the subject matter describedherein may be incorporated;

FIGS. 2-3 are block diagrams that generally represent exemplarycomponents of systems configured to use placeholders in accordance withaspects of the subject matter described herein;

FIGS. 4-5 are flow diagrams that generally represent exemplary actionsthat may occur from a client perspective in accordance with aspects ofthe subject matter described herein; and

FIG. 6 is a flow diagram that generally represents exemplary actionsthat may occur from a cloud storage system perspective in accordancewith aspects of the subject matter described herein.

DETAILED DESCRIPTION Definitions

As used herein, the term “includes” and its variants are to be read asopen-ended terms that mean “includes, but is not limited to.” The term“or” is to be read as “and/or” unless the context clearly dictatesotherwise. The term “based on” is to be read as “based at least in parton.” The terms “one embodiment” and “an embodiment” are to be read as“at least one embodiment.” The term “another embodiment” is to be readas “at least one other embodiment.”

As used herein, terms such as “a,” “an,” and “the” are inclusive of oneor more of the indicated item or action. In particular, in the claims areference to an item generally means at least one such item is presentand a reference to an action means at least one instance of the actionis performed.

Sometimes herein the terms “first”, “second”, “third” and so forth maybe used. Without additional context, the use of these terms in theclaims is not intended to imply an ordering but is rather used foridentification purposes. For example, the phrases “first version” and“second version” do not necessarily mean that the first version is thevery first version or was created before the second version or even thatthe first version is requested or operated on before the second version.Rather, these phrases are used to identify different versions.

Headings are for convenience only; information on a given topic may befound outside the section whose heading indicates that topic.

Other definitions, explicit and implicit, may be included below.

Exemplary Operating Environment

FIG. 1 illustrates an example of a suitable computing system environment100 on which aspects of the subject matter described herein may beimplemented. The computing system environment 100 is only one example ofa suitable computing environment and is not intended to suggest anylimitation as to the scope of use or functionality of aspects of thesubject matter described herein. Neither should the computingenvironment 100 be interpreted as having any dependency or requirementrelating to any one or combination of components illustrated in theexemplary operating environment 100.

Aspects of the subject matter described herein are operational withnumerous other general purpose or special purpose computing systemenvironments or configurations. Examples of well-known computingsystems, environments, or configurations that may be suitable for usewith aspects of the subject matter described herein comprise personalcomputers, server computers—whether on bare metal or as virtualmachines—, hand-held or laptop devices, multiprocessor systems,microcontroller-based systems, set-top boxes, programmable andnon-programmable consumer electronics, network PCs, minicomputers,mainframe computers, personal digital assistants (PDAs), gaming devices,printers, appliances including set-top, media center, or otherappliances, automobile-embedded or attached computing devices, othermobile devices, phone devices including cell phones, wireless phones,and wired phones, distributed computing environments that include any ofthe above systems or devices, and the like.

Aspects of the subject matter described herein may be described in thegeneral context of computer-executable instructions, such as programmodules, being executed by a computer. Generally, program modulesinclude routines, programs, objects, components, data structures, and soforth, which perform particular tasks or implement particular abstractdata types. Aspects of the subject matter described herein may also bepracticed in distributed computing environments where tasks areperformed by remote processing devices that are linked through acommunications network. In a distributed computing environment, programmodules may be located in both local and remote computer storage mediaincluding memory storage devices.

Alternatively, or in addition, the functionality described herein may beperformed, at least in part, by one or more hardware logic components.For example, and without limitation, illustrative types of hardwarelogic components that can be used include Field-programmable Gate Arrays(FPGAs), Program-specific Integrated Circuits (ASICs), Program-specificStandard Products (ASSPs), System-on-a-chip systems (SOCs), ComplexProgrammable Logic Devices (CPLDs), and the like.

With reference to FIG. 1, an exemplary system for implementing aspectsof the subject matter described herein includes a general-purposecomputing device in the form of a computer 110. A computer may includeany electronic device that is capable of executing an instruction.Components of the computer 110 may include a processing unit 120, asystem memory 130, and one or more system buses (represented by systembus 121) that couples various system components including the systemmemory to the processing unit 120. The system bus 121 may be any ofseveral types of bus structures including a memory bus or memorycontroller, a peripheral bus, and a local bus using any of a variety ofbus architectures. By way of example, and not limitation, sucharchitectures include Industry Standard Architecture (ISA) bus, MicroChannel Architecture (MCA) bus, Enhanced ISA (EISA) bus, VideoElectronics Standards Association (VESA) local bus, Peripheral ComponentInterconnect (PCI) bus also known as Mezzanine bus, Peripheral ComponentInterconnect Extended (PCI-X) bus, Advanced Graphics Port (AGP), and PCIexpress (PCIe).

The processing unit 120 may be connected to a hardware security device122. The security device 122 may store and be able to generatecryptographic keys that may be used to secure various aspects of thecomputer 110. In one embodiment, the security device 122 may comprise aTrusted Platform Module (TPM) chip, TPM Security Device, or the like.

The computer 110 typically includes a variety of computer-readablemedia. Computer-readable media can be any available media that can beaccessed by the computer 110 and includes both volatile and nonvolatilemedia, and removable and non-removable media. By way of example, and notlimitation, computer-readable media may comprise computer storage mediaand communication media.

Computer storage media includes both volatile and nonvolatile, removableand non-removable media implemented in any method or technology forstorage of information such as computer-readable instructions, datastructures, program modules, or other data. Computer storage mediaincludes RAM, ROM, EEPROM, solid state storage, flash memory or othermemory technology, CD-ROM, digital versatile discs (DVDs) or otheroptical disk storage, magnetic cassettes, magnetic tape, magnetic diskstorage or other magnetic storage devices, or any other medium which canbe used to store the desired information and which can be accessed bythe computer 110. Computer storage media does not include communicationmedia.

Communication media typically embodies computer-readable instructions,data structures, program modules, or other data in a modulated datasignal such as a carrier wave or other transport mechanism and includesany information delivery media. The term “modulated data signal” means asignal that has one or more of its characteristics set or changed insuch a manner as to encode information in the signal. By way of example,and not limitation, communication media includes wired media such as awired network or direct wired connection, and wireless media such asacoustic, RF, infrared and other wireless media. Combinations of any ofthe above should also be included within the scope of computer-readablemedia.

The system memory 130 includes computer storage media in the form ofvolatile and/or nonvolatile memory such as read only memory (ROM) 131and random access memory (RAM) 132. A basic input/output system 133(BIOS), containing the basic routines that help to transfer informationbetween elements within computer 110, such as during start-up, istypically stored in ROM 131. RAM 132 typically contains data and/orprogram modules that are immediately accessible to and/or presentlybeing operated on by processing unit 120. By way of example, and notlimitation, FIG. 1 illustrates operating system 134, applicationprograms 135, other program modules 136, and program data 137.

The computer 110 may also include other removable/non-removable,volatile/nonvolatile computer storage media. By way of example only,FIG. 1 illustrates a hard disk drive 141 that reads from or writes tonon-removable, nonvolatile magnetic media, a magnetic disk drive 151that reads from or writes to a removable, nonvolatile magnetic disk 152,and an optical disc drive 155 that reads from or writes to a removable,nonvolatile optical disc 156 such as a CD ROM, DVD, or other opticalmedia. Other removable/non-removable, volatile/nonvolatile computerstorage media that can be used in the exemplary operating environmentinclude magnetic tape cassettes, flash memory cards and other solidstate storage devices, digital versatile discs, other optical discs,digital video tape, solid state RAM, solid state ROM, and the like. Thehard disk drive 141 may be connected to the system bus 121 through theinterface 140, and magnetic disk drive 151 and optical disc drive 155may be connected to the system bus 121 by an interface for removablenonvolatile memory such as the interface 150.

The drives and their associated computer storage media, discussed aboveand illustrated in FIG. 1, provide storage of computer-readableinstructions, data structures, program modules, and other data for thecomputer 110. In FIG. 1, for example, hard disk drive 141 is illustratedas storing operating system 144, application programs 145, other programmodules 146, and program data 147. Note that these components can eitherbe the same as or different from operating system 134, applicationprograms 135, other program modules 136, and program data 137. Operatingsystem 144, application programs 145, other program modules 146, andprogram data 147 are given different numbers herein to illustrate that,at a minimum, they are different copies.

A user may enter commands and information into the computer 110 throughinput devices such as a keyboard 162 and pointing device 161, commonlyreferred to as a mouse, trackball, or touch pad. Other input devices(not shown) may include a microphone (e.g., for inputting voice or otheraudio), joystick, game pad, satellite dish, scanner, a touch-sensitivescreen, a writing tablet, a camera (e.g., for inputting gestures orother visual input), or the like. These and other input devices areoften connected to the processing unit 120 through a user inputinterface 160 that is coupled to the system bus, but may be connected byother interface and bus structures, such as a parallel port, game portor a universal serial bus (USB).

Through the use of one or more of the above-identified input devices aNatural User Interface (NUI) may be established. A NUI, may rely onspeech recognition, touch and stylus recognition, gesture recognitionboth on screen and adjacent to the screen, air gestures, head and eyetracking, voice and speech, vision, touch, gestures, machineintelligence, and the like. Some exemplary NUI technology that may beemployed to interact with a user include touch sensitive displays, voiceand speech recognition, intention and goal understanding, motion gesturedetection using depth cameras (such as stereoscopic camera systems,infrared camera systems, RGB camera systems, and combinations thereof),motion gesture detection using accelerometers/gyroscopes, facialrecognition, 3D displays, head, eye, and gaze tracking, immersiveaugmented reality and virtual reality systems, as well as technologiesfor sensing brain activity using electric field sensing electrodes (EEGand related methods).

A monitor 191 or other type of display device is also connected to thesystem bus 121 via an interface, such as a video interface 190. Inaddition to the monitor, computers may also include other peripheraloutput devices such as speakers 197 and printer 196, which may beconnected through an output peripheral interface 195.

The computer 110 may operate in a networked environment using logicalconnections to one or more remote computers, such as a remote computer180. The remote computer 180 may be a personal computer, a server, arouter, a network PC, a peer device or other common network node, andtypically includes many or all of the elements described above relativeto the computer 110, although only a memory storage device 181 has beenillustrated in FIG. 1. The logical connections depicted in FIG. 1include a local area network (LAN) 171 and a wide area network (WAN)173, but may also include phone networks, near field networks, and othernetworks. Such networking environments are commonplace in offices,enterprise-wide computer networks, intranets, and the Internet.

When used in a LAN networking environment, the computer 110 is connectedto the LAN 171 through a network interface or adapter 170. When used ina WAN networking environment, the computer 110 may include a modem 172or other means for establishing communications over the WAN 173, such asthe Internet. The modem 172, which may be internal or external, may beconnected to the system bus 121 via the user input interface 160 orother appropriate mechanism. In a networked environment, program modulesdepicted relative to the computer 110, or portions thereof, may bestored in the remote memory storage device. By way of example, and notlimitation, FIG. 1 illustrates remote application programs 185 asresiding on memory device 181. It will be appreciated that the networkconnections shown are exemplary and other means of establishing acommunications link between the computers may be used.

Placeholders

In accordance with an aspect of the subject matter described herein,placeholders may be used. A placeholder may include a data structurethat represents a file system object. A file system object may be a fileor a directory. A directory may include zero or more files and may be atraditional file directory or some other collection or container offiles. For simplicity, the term file is often used herein, but it is tobe understood that the teachings herein may also be applied todirectories without departing from the spirit or scope of aspects of thesubject matter described herein.

A placeholder may be stored on a local storage device of a machine. Inone implementation, a placeholder may indicate that content associatedwith the placeholder is available in a place other than a file system ofthe machine (hereinafter sometimes referred to as a local file system ora client file system). For example, a placeholder may indicate thatcontent associated with the placeholder is stored in one of the cloudstorage systems illustrated in FIG. 3.

In another implementation, a placeholder may indicate that the contentis accessible through an application that resides on the machine. Thisapplication may store the content in memory, a local file system or aremote file system, may generate the content, may perform a combinationof the above, or the like. Even if the file system could obtain thecontent directly, the file system may still rely on the application toaccess the content of the file.

In one implementation, for a placeholder where the associated content isrelatively small (e.g., less than a predetermined, configurable, orcalculated threshold), a copy of the entire content associated with theplaceholder may also be stored in the placeholder. Storing data “in theplaceholder” is meant to include storing the data in the data structureof the placeholder and/or storing the data in a local storage locationindicated by the placeholder.

Depending on implementation, a placeholder may include various levels ofdetails about a file. At a minimum, a placeholder includes data thatidentifies a file in a remote storage system. For example, a placeholdermay indicate a specific cloud storage system at which the content may befound together with information (e.g., an identifier) that identifiesthe file to the cloud storage system.

A placeholder may include extrinsic metadata and/or intrinsic metadataof a file. Extrinsic metadata is any metadata that is stored outside ofthe content of the file. For example, extrinsic metadata may includename, size, date modified, date created, date last accessed, attributesof the file, version, other metadata maintained by the file system, andthe like.

Intrinsic metadata is any metadata that is stored inside the content ofthe file. For example, for an audio file, intrinsic metadata may includeartist name, album name, year, title of song, rating, tags, comments,genre, length, bit rate, and the like. For an image such as a camerapicture, intrinsic metadata may include, for example, author, datetaken, acquiring program name, dimensions, resolution, bit depth,compression, camera maker, camera model, f-stop, exposure time, otherinformation, and the like.

The examples of intrinsic and extrinsic metadata described above are notintended to be all-inclusive or exhaustive of the types of intrinsic andextrinsic metadata. Indeed, based on the teachings herein, those skilledin the art will readily recognize other extrinsic and intrinsic metadatathat may be used in accordance with the teachings herein withoutdeparting from the spirit or scope of aspects of the subject matterdescribed herein.

In one implementation, a placeholder may include extrinsic metadata of afile such as name of the file, a size of the file, a date that the filewas modified, and a date that the file was created. In anotherimplementation, in addition to the above, a placeholder may also includeattributes of the file.

In another implementation, a placeholder may include some or all of theintrinsic metadata of a file.

In one implementation, a placeholder may include some or all of thesearchable text of a file. For example, a word processing document mayhave content that includes text and formatting. A placeholder mayinclude the beginning N characters, words, paragraphs, pages, or thelike of the text of the word processing document without the formatting,where N is predetermined, configurable, or determined on the fly.

In one implementation, a placeholder may include an indication of thelanguage(s) of the searchable text. For example, a placeholder mayinclude data that indicates that the searchable text is written inEnglish. As another example, a placeholder may include data (e.g., a tagor other data) that indicates that a portion of the text is written inEnglish and data (e.g., another tag or other data) that indicates thatanother portion of the text is written in Spanish.

As another example, a presentation program may have relatively littletext compared to other data used for a presentation. In this example, aplaceholder may include all the text of the presentation while omittingother data used for the presentation.

In one implementation, a placeholder may include a thumbnail of animage. The image may be included in the content of the file associatedwith the placeholder while the thumbnail may be generated from the imageor also included in the content of the file. In one embodiment, thethumbnail included in the placeholder may be of a relatively small sizethat may be predefined, configurable, or determined on the fly.

In one implementation, a placeholder may include data that identifieshow to obtain larger thumbnails of the content associated with theplaceholder. For example, a placeholder may include an address of aservice from which a larger thumbnail of a file may be requested. Theservice may be able to accept input that indicates the size of thethumbnail that is to be provided.

Likewise, in one implementation, a placeholder may include a lowerfidelity sample (or data that identifies how to obtain such as sample)of content of a file associated with the placeholder. For example, aplaceholder may include a lower fidelity sample (or link to a service)of a music, video, or other type of file.

In one implementation, a placeholder may include a data structure (e.g.,a bitmap, linked list, or other data structure) that indicates whichportions of the associated content are located on the local file system.This data structure may be consulted when a program seeks to access thecontent. If the data structure indicates that the requested content isavailable locally, the requested content may be obtained from localstorage. If not, other actions may be taken to obtain the requestedcontent from remote storage prior to providing the program with thecontent.

In one implementation, a placeholder may have a flag that indicateswhether the content of the file is to be made available when offline. Asindicated previously, a client may periodically lose connectivity toremote storage upon which content associated with a placeholder isfound. If the flag is set, when the client is online, content for theplaceholder may be downloaded to local storage and be maintained thereso that the content is available even when the remote storage isunavailable.

Various embodiments may have placeholders that include any one or moreof the data indicated above.

A placeholder may be used to give the illusion that a file resides on alocal file system even when the content of the file resides remotely.This illusion may be maintained even when the remote file system is notreachable. This may be done by inserting the placeholder into anamespace of a local file system. The file system may be modified torecognize placeholders and to display information about a filerepresented by the placeholder as appropriate. For example, the filesystem may display the names and relevant metadata for a placeholderwhen a user navigates through the namespace of the local file system.

Placeholders may be used to vastly reduce the amount of storage spaceconsumed. For example, instead of storing the content for large videoslocally, placeholders may be used to indicate that the videos areavailable. Because the placeholders may use a much smaller amount ofspace than the actual content of the video, even a relatively smalllocal storage device may include placeholders for a vast collection offiles that include a significant amount of content.

Placeholders may be used when a remote storage system is unavailable.For example, when network connectivity is lost or not available, amachine may use locally stored placeholders to navigate and performother operations on the namespace of a file system.

A placeholder is persisted even when the client machine is shutdown.Thus, the placeholder is still available when the client machine isrestarted. This persistence behavior may be implemented by storing theplaceholder on a local storage of the client.

FIGS. 2-3 are block diagrams that generally represent exemplarycomponents of systems configured to use placeholders in accordance withaspects of the subject matter described herein. The componentsillustrated in FIGS. 2-3 are exemplary and are not meant to beall-inclusive of components that may be needed or included. Furthermore,the number of components may differ in other embodiments withoutdeparting from the spirit or scope of aspects of the subject matterdescribed herein. In some embodiments, the components described inconjunction with FIGS. 2-3 may be included in other components (shown ornot shown) or placed in subcomponents without departing from the spiritor scope of aspects of the subject matter described herein. In someembodiments, the components and/or functions described in conjunctionwith FIGS. 2-3 may be distributed across multiple devices.

As used herein, the term component is to be read to include hardwaresuch as all or a portion of a device, a collection of one or moresoftware modules or portions thereof, some combination of one or moresoftware modules or portions thereof and one or more devices or portionsthereof, and the like.

For example, the components illustrated in FIGS. 2-3 may be implementedusing one or more computing devices. Such devices may include, forexample, personal computers, server computers, hand-held or laptopdevices, multiprocessor systems, microcontroller-based systems, set-topboxes, programmable consumer electronics, network PCs, minicomputers,mainframe computers, cell phones, personal digital assistants (PDAs),gaming devices, printers, appliances including set-top, media center, orother appliances, automobile-embedded or attached computing devices,other mobile devices, distributed computing environments that includeany of the above systems or devices, and the like.

An exemplary device that may be configured to implement one or more ofthe components of FIGS. 2-3 comprises the computer 110 of FIG. 1.

A component may also include or be represented by code. Code includesinstructions that indicate actions a computer is to take. Code may alsoinclude information other than actions the computer is to take such asdata, resources, variables, definitions, relationships, associations,and the like.

Code may be executed by a computer. When code is executed by a computer,this may be called a process. The term “process” and its variants asused herein may include one or more traditional processes, threads,components, libraries, objects that perform tasks, and the like. Aprocess may be implemented in hardware, software, or a combination ofhardware and software. In an embodiment, a process is any mechanism,however called, capable of or used in performing an action. A processmay be distributed over multiple devices or a single device. Code mayexecute in user mode, kernel mode, some other mode, a combination of theabove, or the like.

Turning to FIG. 2, the system 200 may include a client 205, a remotestorage system 210, local storage 215, a placeholder 220, and mayinclude other components (not shown). The client 205 may have directaccess to the local storage 215 and be connected to the remote storagesystem 210 through the use of a cloud network.

Although the terms “client” and “server” are sometimes used herein, itis to be understood, that a client may be implemented on a machine thathas hardware and/or software that is typically associated with a serverand that likewise, a server may be implemented on a machine that hashardware and/or software that is typically associated with a desktop,personal, or mobile computer. Furthermore, a client may at times act asa server and vice versa. At times, two or more entities that morefrequently act as a client or server may concurrently be peers, servers,or clients. In an embodiment, a client and server may be implemented onthe same physical machine.

Furthermore, as used herein, each of the terms “server” and “client” mayrefer to one or more physical or virtual entities, one or more processesexecuting on one or more physical or virtual entities, and the like.Thus, a server may include an actual physical node upon which one ormore processes execute, a virtual node upon which one or more processesexecute, a service executing on one or more nodes, a group of nodes thattogether provide a service, and the like. A service may include one ormore processes executing on one or more physical or virtual entities.Furthermore, a single process may implement one or more servers.

The local storage 215 may include any storage media capable of storingdata. For example, the local storage 215 may include volatile memory(e.g., a cache) and non-volatile memory (e.g., a persistent storage).The term data is to be read broadly to include anything that may berepresented by one or more computer storage elements. Logically, datamay be represented as a series of 1's and 0's in volatile ornon-volatile memory. In computers that have a non-binary storage medium,data may be represented according to the capabilities of the storagemedium. Data may be organized into different types of data structuresincluding simple data types such as numbers, letters, and the like,hierarchical, linked, or other related data types, data structures thatinclude multiple other data structures or simple data types, and thelike. Some examples of data include information, program code, programstate, program data, other data, and the like.

The local storage 215 may be external, internal, or include somecomponents that are internal and some components that are external tothe client 205. In one implementation, the local storage 215 may includeany storage that is housed in a machine hosting the client 205. Inanother implementation, the local storage 215 may include storage thatis directly connected to the machine hosting the client 205. Forexample, the local storage 215 may be connected to the machine via a USBlink, an IEEE 1394 link, an optical link, another hard-wired link, orthe like.

The remote storage system 210 may include one or more computers that arearranged to store and provide access to data. Access as used herein mayinclude reading data, writing data, deleting data, updating data, acombination including two or more of the above, and the like. The remotestorage system 210 may be connected to the client 205 via a network suchas the cloud. The cloud is a term that is often used as a metaphor forthe Internet. It draws on the idea that computation, software, dataaccess, storage, and other resources may be provided by entitiesconnected to the Internet without requiring users to know the locationor other details about the computing infrastructure that delivers thoseresources.

In one example, the remote storage system 210 may comprise a data centerwhere the computing devices are located in a single physical location.In another example, the remote storage system 210 may include computingdevices and storage that are attached to the cloud at differentlocations. In one example, the remote storage system 210 may comprise asingle server or other computing device that provides access to one ormore storage devices. In one example, the remote storage system 210 maycomprise a computing device that is not on the client 205's local areanetwork (LAN). In another example, the remote storage system 210 maycomprise any storage that is not housed in or directly connected to theclient 205. In another example, the remote storage system 210 mayinclude storage that is not available to the client 205 when the clientis not connected to a network from which the storage is accessible.

Sometimes the term cloud storage system is used herein. This is notintended to be limiting with respect to remote storage systems to whichthe teachings herein may be applied but to provide an example of aremote storage system that may be used without departing from the spiritor scope of aspects of the subject matter described herein. Whenever theterm cloud storage system is used herein, it is to be understood that inother embodiments, other types of remote storage systems may be usedwithout departing from the spirit or scope of aspects of the subjectmatter described herein.

While the local storage 215 maybe almost continuously available to theclient 205 or may be readily made available by means available to theuser (e.g., by plugging in a connector) the remote storage system 210may, at times, become unavailable to the client 205. For example, if theclient 205 is hosted on a laptop, the laptop may be moved to a locationthat does not have Internet access. As another example, network outagesmay disrupt the connectivity of the client 205 to the remote storagesystem 210. As another example, the remote storage system 210 may becomeinoperative or may be shut down or disconnected for maintenance or otherpurposes. Without placeholders, when connectivity with the remotestorage system 210 is lost, the client 205 may not be able to navigatethe namespace or perform operations on a file where the entire filecontent is not available on the local storage 215.

The placeholder 220 illustrates various exemplary data fields that maybe stored in a placeholder stored on the local storage 215. Althoughonly one placeholder is shown in FIG. 2, more often, there will bemultiple placeholders stored on the local storage 215. For example, fora given namespace, there may be one placeholder for each remote filesystem object if the content of the remote file system object does notcompletely exist on the local storage 215. As another example, for thegiven namespace, there may also be placeholders for remote file systemobjects even when the entire content of the remote file system objectsexists on the local storage 215. This second set of placeholders mayalso be stored on the local storage 215 for files having content with asize less than a given threshold as mentioned previously.

A namespace may include an identifier (e.g., name or other identifier)for each file of a file system together with hierarchy informationregarding the file. For example, a namespace may include a namespaceentry corresponding to D:\DIR1\FILE1.TXT. This namespace entry indicatesthe name of a file (e.g., FILE1.TXT) and indicates that the file existsin a directory (e.g., DIR1). A namespace may also include othermetadata. A namespace may have a one-to-one or some other mapping withfile system information and may represent virtual folder hierarchies.

Searching

As mentioned previously, there may be various reasons to avoid storingall files of a user on each device of the user. With the use ofplaceholders, a file may be completely hydrated, partially hydrated, ordehydrated. When an application on a client requests content of a filethat does not exist on the client file system, the content may beobtained from a cloud storage system.

To completely hydrate a file, in one implementation, content of the filerepresented by a placeholder may be downloaded and stored on the clientfile system. The entire content of a file may be downloaded in a singledownload or may be streamed to the client 305. Upon being completelyhydrated, in one implementation, the placeholder may be purged from thelocal file system and replaced with regular file system metadata. Inanother implementation, even though the contents and metadata of a fileare stored on the client file system, the placeholder may remain and beused in conjunction with or instead of the regular file system metadatamaintained for the file.

When a file is partially hydrated, this indicates that at least aportion of the content of the file represented by a placeholder isstored on the client file system. As indicated earlier, a data structureof the placeholder may indicate which portions of the file are stored onthe client file system and which portions of the file are not stored onthe client file system. In one implementation, at least as long as afile is partially hydrated, a corresponding placeholder remains on theclient file system.

When a file is dehydrated, other than intrinsic metadata, if any,included in the content (and stored in the placeholder), the content ofthe file is not stored on the client file system.

Turning to FIG. 3, the system 300 may include a client 305, a cloud 310,cloud storage systems 315-317, a file store 320, a search store 321, andother components (not shown). The client 305 may include a file manager325, a synchronization manager 326, a placeholder manager 327, agatherer/updater 328, a query manager 329, and other components (notshown).

The components of FIG. 3 may be implemented using the hardware and/orsoftware of one or more computing devices as described previously. Inone implementation, the local store 320 and the search store 321 may beimplemented by a single file system. In another implementation, thelocal store 320 and the search store 321 may be implemented by separatefile systems. The storage device(s) that implement the local store 320and the search store 321 may be implemented in a similar manner as thelocal storage 215 of FIG. 2 and may be external, internal, or includesome components that are internal and some components that are externalto the client 305.

The local store 320 may have computer storage elements that persist(e.g., put in non-volatile storage) file system metadata for local filesystem objects of a local file system of the client and that persistplaceholders for remote file system objects of a cloud storage system.As mentioned previously, the placeholders may include metadata of theremote file system objects without requiring that content of the remotefile system objects exist in the local store 320.

The search store 321 may have computer storage elements that persist asearch database that includes search information from the local filesand from the placeholders. The search database may comprise a relationaldatabase, an object-oriented database, a hierarchical database, anetwork database, another type of database, some combination orextension of the above, and the like. Data stored in a database may beorganized in tables, records, objects, other data structures, and thelike. The data stored in a database may be stored in dedicated databasefiles, dedicated hard drive partitions, HTML files, XML files,spreadsheets, flat files, document files, configuration files, otherfiles, and the like. A database may reference a set of data that isread-only to the database or may have the ability to read and write tothe set of data.

Data in a database may be accessed via a database management system(DBMS). A DBMS may comprise one or more programs that controlorganization, storage, management, and retrieval of data of a database.A DBMS may receive requests to access data in a database and may performthe operations needed to provide this access. Access as used herein mayinclude reading data, writing data, deleting data, updating data, acombination including two or more of the above, and the like.

In describing aspects of the subject matter described herein, forsimplicity, terminology associated with a particular type of databasemay sometimes be used herein. Although particular database terminologymay be used herein, the teachings herein may also be applied to othertypes of databases including those that have been mentioned previously.

The metadata included in placeholders stored in the local store 320 maybe sufficient to allow the client 305, while offline with respect to acloud storage system, to obtain namespace information from theplaceholders. In one implementation, at a minimum, sufficient metadatamay include a name of the file system object. For example, with the nameof the file system object and hierarchy information maintained in thefile system, a user may navigate a namespace of the client file systemeven when the client is offline with respect to a cloud storage system.In other implementations, the metadata included in the placeholders mayalso include other metadata, intrinsic or extrinsic, of file systemobjects.

The file manager 325 may be structured to create, via the file systemmetadata and the placeholders, a namespace that includes the local filesystem objects and the remote file system objects. The file manager 325may be further structured to provide, via an interface, metadata for thelocal file system objects and the remote file system objects regardlessof whether connectivity exists to a cloud storage system.

In absence of connectivity to a cloud storage system, the file manager325 may still allow operations to proceed on both files that residelocally and files represented by placeholders. For example, the filemanager may update a file system data structure of the local file systemto indicate an operation performed on a file system object representedby a placeholder even when the content of the file system object doesnot reside completely on the local store. As another example, the filemanager 325 may update a namespace to reflect an operation such as arename, move, delete, restore, create, copy operation, or the like.

The synchronization manager 326 may be structured (e.g., includehardware and/or software) to discover changes (e.g., content changes,metadata changes including intrinsic, extrinsic, and namespace changes,other changes, and the like) that occurred to file system objects in theabsence of connectivity to the cloud storage system and, whenconnectivity is re-established with the cloud storage system, tosynchronize the changes with the cloud storage system.

In different implementations, the synchronization manager 326 may usevarious methods for discovering changes. For example, in oneimplementation, the synchronization manager 326 may discover changes byexamining an operations log that stores operations that occur on filesystem objects. As another example, in another implementation, thesynchronization manager 326 may discover changes by comparing a state offile system and file system objects prior to the changes with a state ofthe file system and file system objects after the changes.

The placeholder manager 327 may be structured to create, populate, andmaintain the placeholders to ensure that a placeholder exists for eachremote file system object in the namespace at least if the content ofthe remote file system object does not completely exist on the localstore 320. As mentioned previously, a placeholder may also be maintainedon the local file system when the content of the remote file systemobject does completely exist on the local store 320.

The gatherer/updater 328 and/or other components of the client 305 maybe structured to gather search data for file system objects andplaceholders that exist on the local store and to use the gatheredsearch data to update a database that resides on the search store 321.

The query manager 329 may receive and handle queries using the databasethat resides on the search store 321.

Some exemplary actions that may be performed by the gatherer/updater328, the query manager 329, and/or other components of the client 305include:

1. Receiving metadata for a file system object that is represented by aplaceholder. The placeholder is stored on a local file system of theclient. The placeholder includes data that identifies a cloud storagesystem from which content of the file system object is obtainable.

2. Storing the metadata in the placeholder. As mentioned previously,placeholders may be used to store intrinsic and extrinsic metadata offile system objects whose content does not reside on the client filesystem.

3. Obtaining search data from the metadata. Search data may beidentified and obtained from the metadata. In one embodiment, all of themetadata may be used as search data. In another embodiment, some of themetadata (e.g., text, date, and other relevant fields) may be used forsearch data while the rest of the metadata (e.g., numbers, bitmaps, andthe like) may be omitted as search data.

4. Representing the search data in a search database that resides on thelocal file system of the client. The search data obtained from themetadata may then be represented in the search database. Therepresentation may indicate, for example, that the search data wasobtained from a certain file represented by an indicated placeholder.

5. While the client is offline with respect to the cloud storage system,receiving a search request. In response to the search request, thesearch database of the local file system may be searched. In searchingthe search database, a file that is represented by a placeholder may beidentified as being relevant to the search request. An indication (e.g.,a name or other identifier and perhaps other metadata about the file)may be provided as an indication of the file.

The client may be offline with respect to multiple cloud storage systemsthat store content for placeholders that reside on the client filesystem. In this condition, the client may receive a search request andsearch the search database for relevant files. Using the searchdatabase, the client may find at least one file that resides completelyon the client file system while finding two or more files for whichcontent is available on different ones of the cloud storage systems. Theclient may then display an indication of each relevant file (the onesthat are available locally and the ones that are represented byplaceholders) together in a single graphical interface.

Along these lines, while the client is offline with respect to a cloudstorage system, the client may receive a search request that asks forfiles that have at least metadata that satisfies conditions indicated bythe search request. From the search database of the client, the clientmay obtain data that indicates all files that satisfy the conditions.The files may include files that reside on the local file system andfiles that reside in the cloud storage system and that are representedby placeholders that are stored on the local file system. The data forall the files may be provided in a single result set that does notdistinguish between files that reside locally and files that arerepresented by placeholders.

As one example of the above, a client may receive a search request thatasks for a timeline view of all photos taken over a period of time. Inresponse, from the search database, the client may obtain data thatindicates all files that satisfy these conditions. Some of these filesmay have content that completely resides on the local file system whilethe content for others of these files (e.g., files represented byplaceholders) may not completely reside on the local file system. Forthe former files, timeline data may be obtained from file systemmetadata maintained on the local file system. For the latter files,timeline data may be obtained from the placeholders. An ordered timeline(e.g., a sequence from most recent to least recent or vice versa) of allthe found files may be displayed in a single interface that does notdistinguish between files that reside locally and files that arerepresented by placeholders.

Based on the teachings herein, those skilled in the art will recognizemany other query applications of the techniques described herein thatmay be practiced without departing from the spirit or scope of aspectsof the subject matter described herein.

6. Deleting content for a file from a local file system and replacingthe file with a placeholder that indicates that the content is stillavailable on a cloud storage system. When the content of the file isdeleted, the client may refrain from deleting from the search databasesearch data that was obtained from the file provided that theplaceholder still exists on the local file system. While the client isoffline, the client may receive a search request. In searching thesearch database, the client may identify the file as having datarelevant to the search request.

7. In addition to, or in lieu of receiving metadata, receivingsearchable text for a file. The searchable text may also be stored inthe placeholder. Search data (e.g., words, phrases, numbers, other text,and the like), may be obtained from the searchable text and stored inthe search database that is stored on the client storage system.

In one implementation, the searchable text may form only a portion ofall the searchable text of the file. For example, in a word processingdocument, the searchable text may include the first N pages where N isconfigurable. In another implementation, the searchable text may includeall of the searchable text of the file.

The searchable text may be extracted from the file by a sender (e.g., aprocess that executes on the cloud storage system) of the searchabletext. For example, the data extractors 330-332 may extract metadata andsearchable text from stored files and provide this data to the client305.

8. Hydrating a file and obtaining additional search data. In conjunctionto hydrating a file, a client may receive a request for content of thefile. The client may obtain the content from a cloud storage system anddelete the placeholder. With the entire content of the file availablelocally, the client may extract additional search data from the contentof the file and may represent the additional search data in the searchdatabase.

The cloud storage systems 315-317 may include one or more storagedevices together with one or more computing devices that provide accessto those storage devices. In one embodiment, a cloud storage system maycomprise a data center where the computing devices are located in asingle physical location. In another embodiment, a cloud storage systemmay include computing devices and storage that are attached to the cloudat different locations. In one embodiment, a cloud storage system maycomprise a single server that provides access to one or more storagedevices. In one embodiment, a cloud storage system may comprise acomputing device that is not on the client's local area network (LAN).In another embodiment, a cloud storage system may comprise any storagethat is not housed in or directly connected to the client.

Although three cloud storage systems are shown in FIG. 2, in otherimplementations, there may be any number of cloud storage systems.

FIGS. 4-6 are flow diagrams that generally represent exemplary actionsthat may occur in accordance with aspects of the subject matterdescribed herein. For simplicity of explanation, the methodologydescribed in conjunction with FIGS. 4-6 is depicted and described as aseries of acts. It is to be understood and appreciated that aspects ofthe subject matter described herein are not limited by the actsillustrated and/or by the order of acts. In one embodiment, the actsoccur in an order as described below. In other embodiments, however, twoor more of the acts may occur in parallel or in another order. In otherembodiments, one or more of the actions may occur with other acts notpresented and described herein. Furthermore, not all illustrated actsmay be required to implement the methodology in accordance with aspectsof the subject matter described herein. In addition, those skilled inthe art will understand and appreciate that the methodology couldalternatively be represented as a series of interrelated states via astate diagram or as events.

FIGS. 4-5 are flow diagrams that generally represent exemplary actionsthat may occur from a client perspective in accordance with aspects ofthe subject matter described herein. Turning to FIG. 4, at block 405,the actions begin.

At block 410, metadata and/or searchable text is received for a filethat is represented by a placeholder. For example, referring to FIG. 3,the client 305 may receive metadata for a file that is represented by aplaceholder where the placeholder is stored in the local store 320.

At block 415, the metadata and/or searchable text is stored in theplaceholder. For example, referring to FIG. 3, the client 305 may storethe received metadata and/or searchable text in the placeholder thatrepresents the file.

At block 420, the metadata and/or searchable text is obtained. Forexample, referring to FIG. 3, in one implementation, thegatherer/updater 328 may obtain the metadata and/or searchable text fromthe placeholder of the local store 320. In another implementation, thegatherer/updater 328 may obtain the metadata and/or searchable text whenthe client 305 receives it from the cloud storage system.

At block 425, the search data is represented in the local searchdatabase. For example, referring to FIG. 3, the client may represent thesearch data in the search store 321.

At block 430, other actions, if any, may be performed. The other actionsmay include, for example, the actions mentioned in conjunction with FIG.3 or other actions described herein.

Turning to FIG. 5, at block 505, the actions begin. At block 510, asearch request is received. For example, referring to FIG. 3, the querymanager 329 may receive a search request from an application (notshown).

At block 515, in response to the search request, a local search databaseis searched. For example, referring to FIG. 3, the query manager 329searches a search database stored on the search store 321.

At block 520, relevant files are identified. For example, referring toFIG. 3, the query manager 329 may identify files that have content thatis stored on the local store 320 and files that have content that is notstored on the local store 320.

At block 525, a result set is provided that includes all relevant filesidentified. For example, referring to FIG. 3, the query manager 329 mayprovide a result set that includes files stored on the local store 320and files that are represented by placeholders where the content is notstored on the local store 320.

At block 530, other actions, if any, may be performed.

FIG. 6 is a flow diagram that generally represents exemplary actionsthat may occur from a cloud storage system perspective in accordancewith aspects of the subject matter described herein. At block 605, theactions begin.

At block 610, a request is received for metadata and/or searchable textof a file. For example, referring to FIG. 3, the cloud storage system315 may, from the client 305, receive a request for metadata and/orsearchable text for a placeholder stored on the client 305.

At block 615, the metadata and/or searchable text is provided. Forexample, referring to FIG. 3, the cloud storage system 315 may providethe requested metadata and/or searchable text to the client 305.

At block 620, other actions may occur. Other actions may include, forexample, obtaining the metadata from intrinsic or extrinsic metadata ofthe file. Other actions may also include, for example, obtainingsearchable text from content of the file.

As can be seen from the foregoing detailed description, aspects havebeen described related to file system placeholders. While aspects of thesubject matter described herein are susceptible to various modificationsand alternative constructions, certain illustrated embodiments thereofare shown in the drawings and have been described above in detail. Itshould be understood, however, that there is no intention to limitaspects of the claimed subject matter to the specific forms disclosed,but on the contrary, the intention is to cover all modifications,alternative constructions, and equivalents falling within the spirit andscope of various aspects of the subject matter described herein.

What is claimed is:
 1. A method implemented at least in part by acomputer, the method comprising: receiving metadata for a file systemobject that is represented by a placeholder, the placeholder beingstored on a local file system of a client, the placeholder includingdata that identifies a remote storage system from which content of thefile system object is obtainable, the client structured to synchronizethe local file system with the remote storage system, the metadatasufficient to allow the client, while offline with respect to the remotestorage system, to obtain namespace information about the file systemobject from the placeholder; storing the metadata in the placeholder;obtaining search data from the metadata; and representing the searchdata in a search database that resides on the local file system, thesearch database also representing search data from file system objectsthat are stored on the local file system;
 2. The method of claim 1,further comprising, while the client is offline with respect to theremote storage system, performing actions, the actions comprising:receiving a search request; searching the search database in response tothe search request; identifying, from the search database, the filesystem object that is represented by the placeholder as having datarelevant to the search request; and providing an indication of the filesystem object.
 3. The method of claim 1, further comprising:representing a second file system object of the local file system with asecond placeholder, the second file system object having content storedon the remote storage system and the local file system; deleting contentof the second file system object from the local file system; refrainingfrom deleting from the search database search data obtained from thesecond file system object; and while the client is offline with respectto the remote storage system, performing actions, the actionscomprising: receiving a search request, searching the search database,and identifying, from the search database, the second file system objectthat is represented by the second placeholder as having data relevant tothe search request.
 4. The method of claim 1, further comprising:receiving searchable text for the file system object, the searchabletext part of the content of the file system object; storing thesearchable text in the placeholder; obtaining search data from thesearchable text; and representing the search data from the searchabletext in the search database.
 5. The method of claim 4, wherein thesearchable text has a size that is less than all searchable text of thefile system object, the size determined by a configurable setting. 6.The method of claim 5, wherein the file system object comprises adocument and the size is a number of words starting at the beginning ofthe document.
 7. The method of claim 4, wherein the searchable text wasextracted prior to the receiving the searchable text, the searchabletext being extracted by a sender of the searchable text by includingtext and omitting other data included in the content of the file systemobject.
 8. The method of claim 1, further comprising: receiving arequest for the content of the file system object; obtaining the contentof the file system object from the remote storage system; deleting theplaceholder; extracting additional search data from the content of thefile system object; and representing the additional search data in thesearch database.
 9. The method of claim 1, further comprising, while theclient is offline with respect to a plurality of remote storage systems,performing actions, the actions comprising: searching the searchdatabase that resides on the local file system; finding, in the searchdatabase, an indication of a plurality of relevant file system objects,at least one of the relevant file system objects residing on the localfile system and at least two of the relevant file system objectsresiding on different ones of the remote storage systems; and displayingan indication of each of the relevant file system objects together in asingle graphical interface.
 10. The method of claim 1, furthercomprising while the client is offline with respect to the remotestorage system, performing actions, the actions comprising: receiving asearch request that asks for file system objects that have at leastmetadata that satisfies conditions indicated by the search request; fromthe search database, obtaining data that indicates all file systemobjects that satisfy the conditions, the all file system objectsincluding a first set of file system objects and a second set of filesystem objects, the first set of file system objects residing on thelocal file system, the second set of file system objects residing on theremote storage system and represented by placeholders that are stored onthe local file system; and providing the data for both the first set offile system objects and the second set of file system objects in asingle result set.
 11. The method of claim 1, wherein the search requestadditionally asks for an indication of file system objects that includesearchable text that satisfies additional conditions, the placeholdersincluding searchable text that comes from content of the second set offile system objects.
 12. The method of claim 1, while the client isoffline with respect to the remote storage system, performing actions,the actions comprising: receiving a search request that asks for atimeline view of all photos taken over a period of time; from the searchdatabase, obtaining an indication of all file system objects thatsatisfy the search request, the all file system objects including afirst set of file system objects and a second set of file systemobjects, the first set of file system objects residing on the local filesystem, the second set of file system objects residing on the remotestorage system and represented by placeholders that are stored on thelocal file system; for the first set of file system objects, obtainingfirst timeline data from file system metadata maintained on the localfile system; for the second set of file system objects, obtaining secondtimeline data from the placeholders; and displaying output data of theall file system objects in a sequence determined by the first timelinedata and the second timeline data such that the output data indicatesthe photos ordered from most recent to least recent.
 13. In a computingenvironment, a system, comprising: a file store having computer storageelements structured to persist file system metadata for local filesystem objects of a local file system and to persist placeholders forremote file system objects of a remote storage system, the placeholdersincluding metadata of the remote file system objects without requiringthat the remote file system objects exist in the file store; a searchstore having computer storage elements structured to persist a searchdatabase that includes information from the local file system objectsand from the placeholders; a placeholder manager structured to create,populate, and maintain the placeholders to ensure that placeholdersexist in the file store for the remote file system objects in anamespace at least if the remote file system objects do not completelyexist on the file store; and a gatherer/updater, hosted on a client, thegatherer/updater structured to perform actions, comprising: receivingmetadata for a file system object that is represented by a placeholder,the placeholder being stored on the file store, the placeholderincluding data that identifies the remote storage system from whichcontent of the file system object is obtainable, obtaining search datafrom the metadata, and representing the search data in the searchdatabase.
 14. The system of claim 13, further comprising: a querymanager that, at least while the client is offline with respect to theremote storage system, is structured to perform actions, comprising:receiving a search request; in response to the search request, searchingthe search database; identifying the file system object that isrepresented by the placeholder as having data relevant to the searchrequest; and providing an indication of the file system object.
 15. Thesystem of claim 13, wherein the gatherer/updater is further structuredto add additional search data to the search database when additionalcontent of the file system object is received and to refrain fromdeleting the additional search data from the search database even afterthe additional content of the file system object is deleted from thefile store provided that the placeholder still exists on the file store.16. The system of claim 13, wherein the gatherer/updater is furtherstructured to perform additional actions, the additional actionscomprising: receiving searchable text for the file system object fromthe placeholder, the searchable text previously obtained from thecontent of the file system object; obtaining search data for thesearchable text; representing the search data for the searchable text inthe search database.
 17. The system of claim 13, further comprising aquery manager structured to perform additional actions at least whilethe client is offline with respect to the remote storage system, theadditional actions comprising: receiving a search request that asks forfile system objects that have metadata that satisfies conditionsindicated by the search request; from the search database, obtainingdata that indicates all file system objects that satisfy the conditions,the all file system objects including a first set of file system objectsand a second set of file system objects, the first set of file systemobjects residing on the local file system, the second set of file systemobjects having content that resides on the remote storage system andbeing represented by placeholders that are stored on the local filesystem; and providing the data for both the first set of file systemobjects and the second set of file system objects in a single resultset.
 18. A computer storage medium having computer-executableinstructions, which when executed perform actions, comprising: receivinga request for search data of a file system object indicated by a client,the client having a client file system, the client file system havingfile system objects in which all content is located on the client filesystem and file system objects in which less than all content is locatedon the client file system, the client having placeholders that representat least the file system objects in which less than all content islocated on the client file system, the file system object beingrepresented by a placeholder stored on the client file system, theplaceholder identifying a remote storage system from which content ofthe file system object is obtainable, the client structured to store thesearch data in a search database of the client file system even when thecontent of the file system object is not stored on the client filesystem; and providing the search data of the file system object from theremote storage system.
 19. The computer storage medium of claim 18,further comprising, prior to providing the search data, obtaining thesearch data from metadata of the file system object, the metadata storedon the remote storage system.
 20. The computer storage medium of claim18, further comprising, prior to providing the search data, obtainingthe search data from content of the file system object, the contentstored on the remote storage system but not on the client file system,the extracting comprising obtaining text from the content whilediscarding non-text from the content.